介词短语相当于一个形容词或副词,可用作状语、定语和表语。如：The man came .(状)(那个人走下楼来)/The woman is from the countryside.(定)(头上戴花的妇女来自乡下)/The teacher is now with the pupils.(表)(老师现在和学生在一起)

4、介词短语在句子中的位置：

介词短语做状语时,如果表示时间/地点,可以放在句首或句尾,如果表示方向/方式/伴随/涉及/原因/目的/比较,一般放在句尾; 介词短语作表语时放在连系动词之后;介词短语作定语时,只能放在被修饰的名词之后。如：He wanted to find a good job in Shanghai the next year.(状语)(他想来年在上海找份好工作)/ They searched the room for the thief.(他们在房间里搜索小偷) / The letters are for you.(表语)(信是给你的)/ Have you seen a cat with a black head and four white legs?(定语)(你看见一只黑头白腿的猫了吗?)

5、重要注释：

⑴ this / that / these / those / last / next / a / every / each等词构成的时间短语,前面不用任何介词。如：Every year travellers from abroad come to visit Pingyao.(每年都有国外的游客来游览平窑镇)/ He had a bad cold that week.(那个星期他患重感冒)

⑵ for有时用来引出动词不定式的逻辑主语,常翻译成“对于…而言”。如：It’s too hard for me to finish the work in only one hour.(让我在区区一个小时内完成这项工作太难了)/ The house is big enough for 10 men to live in.(房子够大的可以容10个人住)

⑶ of有时用来表示后面的人物正好是前面的表语的逻辑主语。如：It’s very nice/kind of you to do so.(你这么做真是太好了)

⑷ 介词有时会与它的宾语分离,而且宾语前置。

① 当宾语是疑问词时。Who are you talking about?(你们在谈论谁?)

② 宾语在从句中当连接词时。He has a younger brother who he must take good care of.(他有 一个需要他照顾的小弟。) / Do you know who our teacher is talking with over there?(你知道我们的老师在那边和什么人谈话吗?)

③ 动词不定式作定语且该动词为不及物动词,后面有介词。I finally found a chair to sit on.(我 最终找到了一张椅子坐。)

(5) 记住一些固定词组：arrive at/in(到达…),on foot(步行),not…at all(根本不),to the north of(在…以北),in the east of(在…的东部),in the night(在夜间),at night(在晚上),be afraid of(害怕…),be full of(充满/ 装满….),be filled with(充满/ 装满….),be good/bad for(对…有益/有害),be made of(由…做成),be made from(由…制造),play with(玩耍……),look out of(朝…外面看),at the end of(在…末梢/结束时),by the end of(不迟于…/到…末为止),with the help of或with one’s help(在…的帮助下),look after(照料…),look for(寻找…),on a bike(=by bike)骑车, help sb. with(帮某人做…),get on (well) with(与某人相处[融洽]),等等。